Many types of endoscopes currently use a fiber optic viewing bundle that cooperates with a focusing eyepiece assembly to permit viewing within a body cavity. The fiber optic bundle and any associated connectors can be generally referred to as a viewing assembly. The fiber optic bundle usually includes an image bundle that is a coherent bundle of image carrying fibers and at least one illumination carrying bundle or fiber. The image bundle typically cooperates with the focusing eyepiece. The end of the image bundle usually terminates in a connector that cooperates with the eyepiece.
The illumination fibers are typically adapted to cooperate with a light source. The ends of the image bundle and the illumination fibers are usually coterminal at the distal end of the endoscope. The illumination fibers carry light from a light source to the distal end of the endoscope in order to illuminate the area in front of the endoscope. An image of the illuminated area is then carried back through the endoscope to the eyepiece via the image bundle.
Many versions of endoscopic devices also include a handle that holds the eyepiece and the fiber optic bundle and associated connectors. Some hand held endoscopic viewing devices include a power source and a light source associated with the handle. Also, the handle can be configured to connect to the fiber optic bundle and to the eyepiece to hold the entire system in operable relationship.
The eyepiece assembly of a typical endoscope can be used with the naked eye of the operator or, alternatively, can be configured to connect to a camera or an electronic monitor to provide still photographs or video images. Focusing eyepieces generally include precision optics and moving parts such as rotating rings or sliding tubes. The spacing between the end of the image bundle or connector and the eyepiece must be exact for proper focus. These instruments are generally made with precision components and are therefore relatively expensive and can be very delicate. Also, the step of focusing the eyepiece takes time and requires additional manipulation of the endoscope. This can be a disadvantage in emergency situations. A fixed-focus eyepiece that is quickly and easily cleaned, assembled, and used provides a great advantage.
Another advantage of a viewing system that can be disassembled into various parts such as the viewing assembly, the eyepiece assembly, and the handle is that each separate part can be replaced if necessary. Typically, fiber optic components that are used in the viewing assemblies are somewhat delicate and have a limited life span. For example, the fiber optic bundles are often bent or twisted during use. The repeated stresses of bending and twisting can cause the optic fibers to break. However, as components are removed and replaced it is often necessary to refocus the endoscope before it can be used.
It is desirable to provide a viewing assembly that includes a minimal number of parts that can be relatively inexpensive to replace. Also, the replaceable components should be easily manufactured in order to keep the cost of the replaceable parts as low as possible. Given the precise nature of most endoscopes, it would be an advantage to provide an endoscopic viewing system that is more easily manufactured.
Many common endoscopes are also relatively complicated in structure. Since endoscopes are typically used for sterile surgical procedures, the complicated structure makes sterilization of the instrument difficult. Also, some sterilization procedures are harmful to eyepiece optics and other more delicate components. It would therefore be an advantage to provide an endoscopic viewing assembly that is relatively simple to manufacture and use and that is easily sterilized. A simplified, fixed focus eyepiece assembly that has no moving parts and that is sealed from the outside world would also be an advantage.
Accordingly, what is needed is an endoscopic viewing system that allows for relatively easy replacement of any particular component that may become dirty, contaminated, or damaged during use. The portion of the device that comes in contact with the patient should be separately sterilizable to avoid damage to eyepiece optics. The present invention meets these desires.